In the past ten years, diffractive optics technology evolved from a novel area of research to a new and powerful tool for optical designers. Major technical advances in diffractive optics technology include low cost alternatives to aspheric lenses, new solutions to aberration correction of refractive optic elements, and new devices such as moth's eye structures and beam multiplexers.
Conventional fabrication techniques for diffractive optics include diamond turning, semiconductor mask/etch processing, and injection molding. Except for injection molding, these fabrication techniques are very expensive, and injection molding is only applicable to fabricating plastic diffractive optics. Conventional master fabrication techniques are typically limited to covering areas from a few square inches to less than a square centimeter depending on the complexity and aspect ratio of diffractive pattern. With a process for integrating smaller master elements into larger area masters we can make the crucial advancement of the practical application of diffractive optics to polarizers for visual displays applications.